Adjustable vehicle suspension



Feb. 20, 1940.

A. 5. KROTZ ADJUSTABLE VEHICLE SUSPENSION Filed Oct. 12, 19157 5Sheets-Sheet 1 Mag i Feb. 20, 1940. A. s. KROTZ ADJUSTABLE VEHICLESUSPENSION 5 Sheets-Sheet 2 Filed Oct. 12, 1937 5 IIIIIIIITIIIIIIIIIIIIIFeb. 20, 1940. A. s. KROTZ 2,191,211

ADJUSTABLE VEHICLE SUSPENSION Filed Oct. 12, 1937 5 Sheets-Sheet 5 Feb.20, 19 40. A, s, KRQTZ 2,191,211

ADJUSTABLE VEHICLE SUSPENSION Filed Oct. 12, 1957 5 Sheets-Sheet 4 3' I+S 0 $1 ml OEI- r O 2 -K m I Jam-1227a 272M if Feb. 20, 1940. A. s.KROTZ 2,191,211

ADJUSTABLE VEHICLE SUSPENSION Filed Oct. 12', 1937 5 Sheets-Sheet 5 rPatented Feb. 20, 1940 UNITED ADJUSTABLE VEHICLE SUSPENSION Alvin S.Krotz, Akron, Ohio, assignor to The B. F. Goodrich Company, New York, N.Y., a corporation of New York Application October 12, 1937, Serial No.168,533

'7 Claims.

This invention relates to suspension systems for vehicles and it isapplicable to vehicles generally including passenger automobiles, motorbuses, trucks, trailers, and railway cars wherein an elastic suspensionsystem is used for cushioning the movement of the vehicle over theirregularities of road-bed or track.

Some vehicles are operated under considerable variations in load, forexample motor buses are operated at times with no passengers or only afew and at other times with a capacity load. Inasmuch as the variationin the amount of load is often a large proportion of the total load onthe suspension system there has heretofore been the objection that undermaximum load the available range of springing movement has been reducedundesirably, at times even to nothing so that the body of the vehiclehas been caused to bump against under structure. It has been necessaryin many cases to use excessively stiff springs so that the ride has beenuncomfortable, especially at light loads.

The chief objects of the present invention are to provide formaintaining an adequate range of springing movement under all conditionsof load by maintaining the vehicle body at a constant or substantiallyconstant height with respect to the wheels; to provide for softness ofspringing despite large variations in load; to provide for effectingadjustment of the height of the body with respect to the wheels; toprovide for effecting such adjustment automatically; to provide foreffecting automatic adjustment under control of the operator; to providefor convenient manual operation to eflect the adjustment, and to providesturdiness of construction and reliability of operation.

These and other objects will be apparent from the following description,reference being had to the accompanying drawings in which: v

Fig. 1 tea front elevation with parts sectioned and broken away or afront or steering wheel assembly mounted on a body frame and embodyingand constructed in accordance with the invention.

Fig. 2 is a view taken along the line 2-2 of Fig. 1.

\ Fig. 3 is a section taken along the line 3-3 of Fig. 2.

Fig. 4 is an elevation of electrical control mechanismas viewed from theright in Fig. l.

Fig. 5 is a diagram of the electrical circuit of away and sectioned of amodified form of suspension embodying and made in accordance with theinvention.

Fig. 7 is a section taken along the line 1-1 of Fig. 6. q r

Fig. 8 is a perspective view of a portion of the structure of Fig. 6.

Fig. 9 is a plan view, with parts broken away and sectioned, of achassis frame and a further modified form of suspension system embodyingand made in accordance with the invention.

' Fig. 10 is a' view taken along the line lm-lfl of Fig. 9.

Fig. 11 is a view taken along the line ll--i l of Fig. 10.

Fig. 12 is an elevation with parts broken away and sectioned, the viewbeing partly diagrammatic, of the pressure-fluid operating andcontrolling mechanism of Fig. 9.

Fig. 13 is an elevation like Fig. 11 but showing a further modifiedconstruction embodying and made in accordance with the invention.

Fig. la is a vertical section as seen from the front of a pneumaticsuspension embodying and made in accordance with the invention.

Fig. 15 is a view taken along the line i5, it of Fig. 14.

Fig. 16 is a vertical section as seen from the side of a still furthermodified form of suspension embodying and made in accordance with theinvention.

The invention in several of its phases is applicable generally tosuspension systems whether the wheel assemblies be mounted individuallyor in pairs or groups. In the embodiment of Fig. l the invention isillustrated as applied to an independent suspension of a, constructionthat is described more fully and claimed in my copending applicationSerial No. 111,424, filed November 13, 1936, for Vehicle wheel mounting.wherein the springing is provided by one or more resilient rubbertorsion bushing assemblies adapted to transmit supported load bytorsional stress on the rubber. In the embodiment of Figs. 1 to 5 anelement of the rubber bushing assembly is utilized to vary the height ofthe vehicle body with relation to thewheels. A transverse frame member20 of the body carries longitudinal frame member 2|, an upper mounting22 and a lower an eye of an upper link member 28 and the lower bushingassembly 25 is thus held within the eyes of the spaced-apart arm of awish-bone link member 29. The outer ends of the link members 28 and 29have ball and socket connections to a member 30 having fixed to it awheel axle 3| upon which is rotatably mounted a wheel structure 32 and adirect-acting shock absorber 33 may be connected to the link members toact in series with the rubber of at least one of the torsion bushings ina manner more fully described in my co-pending applicationabove-identified.

The upper torsion bushing assembly may be provided with a toothedmounting 34 of its inner element within the support 22 for the purposeof rotatably adjusting the bushing in its mounting to adjust the heightof the body with respect to the wheels, this adjustment being one which.is adapted to be made in the factory or shop but is not suitable foraccomplishment while the vehicle is under load and especially when it isin oper ation.

In accordance with the present invention I provide in the embodiment ofFigs. 1 to 5 for adjusting the bushing while the vehicle is under load,and provision is made for effecting the adthe load by means of a tensionrod 36 disposedcrosswise of the vehicle and pivotally connected at itsouter end to the lever arm 35 and having a threaded engagement with aturnbuckle or nut member 31 mounted at an intermediate position upon theframe member 20 for rotation of the nut member 31 within a bearing 38secured to the frame member. The structure thus far described with theexception of the nut member 31, may be duplicated at the other side ofthe 'vehicle and a tension rod 39 of the other assembly may be extendedalso to have a threaded engagement with this nut member. The nut memberand the tension rod 36 and 39 are threaded in opposite directions sothat rotation of the nut member moves the tension rods inwardly togetheror outwardly together. Such movement of the tension rods 36 and 39causes a rotative movement of the inner element 21 and a correspondingmovement of the inner element of the lower bushing at the other side ofthe vehicle so that the height of the body is changed simultaneouslywith respect to the two wheel assemblies.

A reversible electric motor 40 provides power means for rotating the nut31 in both directions to move the tension rods 36 and 39 in and out toeffect the height adjustment, the nut 31 preferably being provided witha gear wheel 4| attached to the nut member and meshing with a upon theframe member 2| in a position to be operated by a vertically mountedswitch-operating cam rod 45. The rod at its upper end may slide in abearing 46 carried by the frame and at its lower end have a pivotalconnection with an arm 41 secured to the outer movable element of thelower bushing assembly so that the arm 41 partakes of the movement orthe lower link member 23. As is shown in Fig. 5 the electrical circuitthrough the motor and the two switches 43 and 44 is such that uponclosing of the upper switch 43 the motor is caused to rotate in onedirection and upon opening of that switch and closing of the lowerswitch 44 the motor is caused to rotate in the opposite direction. Abutton or other manual type switch 48 may be provided in the power line,preferably at a position convenient to the operator of the vehicle, forrendering the automatic height adjusting mechanism operative orinoperative at will.

It will be understood from the foregoing description that normally theswitches 43 and 44 are open when the motor 40 is stopped so that thevehicle body is maintained at a determinate normal height with respectto the wheels. Upon increasing the load on the vehicle the body of thelatter tends to descend with respect to the cam rod 45 to close theswitch 43, whereupon, assuming that the operator has closed switch 48,the nut 31 will be rotated by the motor 46 in the proper direction toexert an additional pull upon the rods 36 and 39 to rotate the innerelements of the lower bushings in the direction to cause elevation ofthe body with respect to the wheels. This action continues until thebody has risen with respect to the cam rod 45 to a position where switch43 is opened,.whereupon, by the stoppage of motor 46 the mechanism isheld in the adjusted position so that the normal height of the body withrespect to the wheels is maintained constant or approximately constantdespite the increased load. Upon relieving the vehicle of load the bodytends to ascend with respect to the cam rod 45 until by the closing ofswitch 44 i and the motor 40 rotates nut 31 in the opposite directionand the tension rods 36 and 33 are eased outwardly topermit the body todescend with respect to the wheels until the switch 44 is again openedand the motor stopped so that the height relation of the body and thewheels is again restored.

Also, adjustment to overcome the creep or non-elastic yielding of l therubber during use is made possible.

In case a height adjustment of one wheel is desired with respect to thewheel at the oppo- Y non-elastic yielding of the rubber in, use and itpermits adjustment to level the vehicle laterally.

- y In the embodiment of Figs. 6 to Bthe suspension system differssomewhat in details from that of Figs. 1 to 5. In this embodiment eachwheel assembly is resiliently connected tothe frame by a single torsionbushing assembly indicated generally at 50 mounted at the lower side ofa transverse frame member ii. A longitudinal frame member 52 supports ashock absorber 53, the operating link 54 of which constitutes the upperlink of the wheel suspension. A wheel-support ing steering knucklemember 55 carrying a wheel spindle 56 is pivotally connected to the link64 at the outer end of the latter and is likewise pivotally connectedto' the outer end of awlshbone link structure 51, .for steeringmovement. The inner ends of the two arms of the wishbone link 51 aresecured as by welding to outer enclosing elements of the rubber bushingassembly, the outer enclosing element being shown at 58. An outerdiscontinuous sleeve element 58 andpa rubber body 68 are held preferablyradially compressed upon an inner sleeve element 6|, and the rubberpreferably is in vulcanized adhesion with the inner and outer sleeveelements BI and 59. a

For limiting upward movement of the body with relation to the wheel theupper link 64 may be provided with a rubber cushion 62 engageable with abracket 63 secured to the frame, and for limiting downward movement ofthe body with respect to the wheel the lower link structure 51 may beprovided with a rubber cushion 64 engageable with the bottom of theframe.

To enable the rubber bushing assembly to transmit the supported load bytorsional stress on the rubber the inner element 6| of the bushingassembly carries at its forward end an arm 65 the end of which restsupon a supporting structure 66 mounted upon the frame.

The wheel assembly at the opposite side of the vehicle may be similarlymounted and an arm 61 of the latter mounting may also rest upon thesupporting structure 65, the latter being located at an intermediateposition on the frame member 5i.

The supporting structure 56 comprises a vertical guide 68 mounted uponthe frame member. 5| having a vertically movable member 69 spl ned forengagement with a vertically disposed operating screw 92 which issupported for rotation at its upper end as by an anti-friction bearing93. A gear wheel 94 is mounted for rotation with the screw 92, the gear94 meshing with a pinion 95 of a reversible driving motor 96. The motormay be operated by switches 91, 98 through an electric circuit similarto that of Fig. 5, the switches 9'! and 98 in turn being operated by acam 99 which may be carried by one of the outer enclosing elements lidof the bushing assembly so that it swings with the wish-bone link 51 ofthe wheel mounting. The automatic operation to efiect the heightadjustment in this embodiment may be the same as that described for theembodiment of Fig. 1.

In the embodiment of Figs. 6 to 8 adjustment of the height of the wheelassembly with respect to the wheel assembly at the opposite side of thevehicle is effected by means of a plate lull resting upon the flangedbottom end of the member 69. The plate Hill is provided with steppedportions mi, 102, and M33 as shown most clearly in Fig. 8. A number ofvertical positions of one of the arms 65, ill with relation to the otherarm may be obtained including-if desired, the same vertical position forboth by resting the two arms upon the more extensive portion m3 of theplate. The number of variations in the height adjustment of one wheelassembly with respect to the other may be increased by the provision ofan unsymmetrical construction of one or both of the arms 65 and 61 aboutthe longitudinal axis of the arm so that when it is inverted front toback the eflective position of the arm is changed. This may beaccomplished, ior example, by the provision of a greater prominence ofthe projection 65 than the opposite projection 65. For iurtherrefinement oi the adjustment the arms may be attached to the bushings bymeans ci a plurality of bolts 50, 50" permitting many eifectivepositions oi the arms to be obtained especially when this adjustment isused in combination with the reversal feature and the stepped plateiilil.

- In the embodiment of Figs. 9 to 12 provision is made for effecting theadjustment in the height of the body ,with respect to all four wheels ofI the vehicle simultaneously even though each wheel is individuallysprung. In this embodl ment 9. pressure fluid operated system isprovided for effecting the variations in height and provision is madefor manual operation by the operator of the vehicle simply by operationof /the usual foot brake pedal of an hydraulic brake system.

Rear wheels ill], iii are mounted for independent springing upon'avehicleirame M2 by means of respective wish-bone arms Hi3 andillisecured to springs of the torsion rod type H5 and H6 at the rearends of the latter. The torsion rods i i5 and i it are positionedlongitudinally of the vehicle and are rotatably mounted at their frontand rear ends at cross members "i ii and H8 of the frame.

Front wheels H9 and I20 are pivotally mounted for steering uponwish-bone arm's B20, I22 which! are secured to spring torsion rods I23,B26 which are rotatably mounted on the frame H2 at forward bearings I25,I26 and in rear bearings I21, H28 at a cross member i29 of the frame.For resisting rotation of the torsion rods at their ends remote from thewheels the rods have arms I30, i3l, i32 and N3 rigidly secured to therods at such ends. These arms ltd to 133 extend inwardly with respect tothe sides of the vehicle and are adapted to rest upon a supporting plateI34. The plate I 3d is provided with an upwardly extending guide posti355 slideable in a guide I36 mounted upon the cross members H8 and E29of the frame whereby vertical movement of the plate H34 causes acorresponding movement of the arms ldil to lid and 9. raising orlowering of the vehicle frame with respect to all the wheelssimultaneously.

The vehicle is provided with the usual foot brake pedal it'll whichoperates a conventional hydraulic brake system through a pressurecylinder 1138. According to the invention, provision is made forutilizing the pressure fluid of this system for raising and lowering theplate Hid to eflect changes in the height of the body with respect tothe wheels. To this end a master control valve tilt is provided withfluid connections from the hydraulic brake system to an operatingcylinder Mil through an operating valve i d i. The master valve ltdcomprises a casing divided into two compartments by a vertical wall Midthe com-1 partments of which are divided by valved horizontal partitionsMd, Md. Valves Mid Md ltd are spring-pressed upwardly to close, and thestems of the valves project upwardly through the casing where they areadapted to be pressed downward together by an operating member Mil whichmay be positioned to be depressed by the having on its right-handside,.as viewed in Fig.

12, a pressure fluid inlet I52 and a discharge opening I53, and on theleft-hand. side of the casing a pressure fluid exit I54 and a by-passpassage I55. A piston I58 of a height sufficient to cover all theoperations in the. middle position shown is provided within the casingand is apertured at I51 in its top face for passage of fluid to thepiston. A connecting rod I58 is pivoted at its upper end to the pistonand at its lower end to one of the arms of the wish-bone structure I2Iso that as the load on the vehicleis changed the piston I58 operateswithin the chamber of the valve I4 I.

The operating cylinder I40 is provided with a .combination inlet andexit port I59 and has a piston I60 within its casing adapted to transmitthe pressure upon the plate I34 to the body of fluid beneath the pistonthrough a connecting link I6I which may be roundedat both ends to set ina corresponding recess in the bottom of plate I34 and the top of thepiston I to provide for self-alignment.

The inlet I48 of the master valve I39 is connected directly with thepressure line I82 of the hydraulic brake system and the exhaust port I5Iis connected to the reservoir of the hydraulic brake system all bysuitable piping. Suitable piping connections are provided between theports of the master valve I39, the operating valve I and the operatingcylinder I40 all as; shown in Figs. 9, 10 and 12.

The operation of the system is as follows: Assuming the positions of theparts as shown in Fig. vl2 to be the positions for the normally desiredheight of the vehicle body with respect to the wheels, if now the loadon the vehicle is materially increased the body will be caused todescend with respect to the wheels, whereupon the cylinder of theoperating valve I4I will be caused to descend with respect to the pistonI56 thereby opening ports I52 and I54 to the interior of the cylinderand maintaining thetwo upper ports I53 and I55 closed by the sidewall ofthe piston. If now the operator depresses the brake pedal normaloperation of the brakes will follow but operation of the cylinder I40will not occur because the master valve I39 remainsclosed, the springsof these valves maintaining these valves closed. If, however; theoperator depresses the member I41 of the master valve I39 the valve I45will be opened, along with valve I48, and if the brake pedal is. thenoperated pressure fluid will be admitted beneath the piston I60 of theoperating cylinder I40 through the right-handextent or until piston I55against assumes the" position of Fig. 12 whereupon the passage of thepressure fluid to the operating cylinder I40 will be closed and the bodywill remain at that height.

A ball check valve I54 may be provided to maintain the pressure beneaththe piston I80 despite surges in the line. v

lower end of a bell-crank form pivoted at I19 piston I58 will assume alow position with rela- 5 I tion to the cylinder thereof, whereupon theupper ports I53 and I55 will be opened while the lower ports aremaintained closed. If the operating member I41 of the master valve I39is then dopressed pressure fluid will be exhausted from be- 10 neath thepiston of the operating cylinder I40 and will be caused to flow throughthe lay-pass I55, the discharge port I53 and through the lefthandchamber of the master control valve I39 back into the reservoir of thehydraulic brake 15 system,'through ports I50 and III, whereupon the bodywill be caused to drop until the parts of the operating valve I4I againassume the positions of Fig. 12, whereupon the body will be maintainedat that height because the fluid be- 20 neath the piston I50 has nofurther escape.

Because of the large mechanical advantage afforded by the fluid pressuresystem of the hydraulic brake system relatively small effort of theoperator upon the. brake pedal I31 is re- 5 quired to raise the body ofthe vehicle. this arrangement is well suited especially to vehicles likesmall motor buses and passenger automobiles where the load is notexcessively large but is' changed frequently by the getting on and oilof 0 the passengers in groups, and the change in load is a large portionof the total load.

The embodiment of Fig. 13 is adapted especially for vehicles where theload is changed infrequently butin a large proportion of the total 35load as for example in some trucking operations where the truck isusually either heavily loaded or empty and in passenger automobiles. Thetwo-position adjustment is suitable for many such applications. Thisembodiment is illustrated in Fig. 13 as applied to a torsion barsuspension of the construction above described for Fig. 9, two of thetorsion bars being illustrated in Fig. 13 at I10, "I the bars beingpivotally mounted in a transverse frame member I12 of the vehicle. Leverarms I13, I14 are mounted at the ends of the tension rods I10 and HI andare adapted to bear against the supporting plate I15 having an upwardlyprojecting guide post I16 slidable within a guide I11 mounted upon aframe member An over-center linkage is provided for maintaining thesupporting plate I15 either in a lower position for light loads or in anupper position for heavy loads. This linkage may comprise an operatinghandle I18 having a to a bracket I80 mounted on the frame and pivoted atI8I toa link I82 which is pivoted at its "lower end to the top of theguide post I15. The

arrangement is such that by the over-center arrangement of the pivotsthe handle is held either in the full line position-in which thesupporting plate" I15 is held up for maintaining the-vehicle bodyv atthe desired height under heavy loads, or the handle maybe swung to thebroken line position wherein the pivots are over-center in the 65 otherdirection so that the plate 15 is maintained in its lower-most positionfor light loads on the vehicle. If desired, the arrangement may be 7such that the handle I18, extends through the 70 floor I83 of thevehicle in a position to be ated conveniently by the driver.

Referringmow to the embodiment of Fig. 16.

a construction is illustrated in which a two=position adjustment isprovided for a suspension of u operthe leaf" spring type and provisionis made for effecting the adjustment from a position remote from thewheel and spring assembly. A vehicle frame I99 has connected to it atits rear end a leaf spring assembly I9I mounted by means 01 aconventional shackle I92, the spring being connected at its centralpoint to the rear axle housing I93 by means of one or more straps I94.At its forward end the leaf spring I9I is pivoted at I95 to arear'wardly extending arm of a bell crank lever I96 pivoted to the frameat I91. A connecting rod I93 is pivoted to the other arm of the bellcrank which extends downward and the other end of the rod I98 is pivotedto an arm I99 of a bell crank handle lever 299, said lever being pivotedto the frame at 29l. The arrangement is such that in the full lineposition shown, which is for light loads, the spring I9I is held in araised position with respect to the frame and when the lever 299 isswung to the open line position the spring is moved to its lowerposition, or in other words, the body 01 the vehicle is caused to beraised with respect to the wheels. The parts are maintained in each ofthe two positions by the over-center relationship oi the rod I99 withrespect to the pivot 29I Suitable abutments 292 and 293 may be providedfor the two positions of the lever 299. This construction makes possiblethe manipulation of the rear spring of the vehicle by operation at aposition near the drivers seat at the front of the vehicle. It will beunderstood that the construction described may be duplicated on otherwheels of the vehicle and if desired they may be all operated conjointlyby a single operating lever.

In the embodiment of Figs. 14 and 15 provision is made for a pneumaticspring suspension and for automatically controlling the height of thebody with respect to the wheels. In this embodiment a frame member 2I9supports a pneumatic spring cylinder 2 by means of an outwardlyextending bracket structure 2l2. Within the cylinder 2 is disposed apiston 2I3 having upper and lower guide rods 2I4 and 2I5 extendingthrough the ends of the cylinder and providing guided vertical motion ofthe piston and cylinder with respect to each other. The lower piston rod2I5 has secured to it at its lower-most end an arm structure 2I6 whichcarries a wheel spindle 2H for supporting a wheel assembly 2I9.Springing is effected by a confined body of air above the piston 2I3within the cylinder and the space in the cylinder beneath the piston'2i3preferably is vented as at 2 I 9. If desired, a shock absorber 2529,which may be of the direct-acting type, may be associated with the upperpiston rod 2I9. For admitting compressed air to the cylinder space abovethe piston 2I4, and for exhausting air therefrom, the cylinder isprovided with, a port 22!. Compressed air is supplied through a pipeline 222.

For the purpose of providing an automatic adjustment of the height ofthe vehicle body with respect to the wheels a valve assembly 229 isinterposed between the supply line 222 and the port 22!. The operationof this valve being controlled by the height of the body with respect tothe wheels. To this end the valve 223 is provided with a double-endedpiston valve 22% arranged so that the space between the piston ends isalways in communication with the cylinder port Hi. The supply line 222is in connection with the valve through a port 225 adapted to be openedand closed by the upper piston portion. A venting port 229 is providedin the wall of the valve casing in a position to be opened and closed bythe lower valve end. A rod 221 or the piston 224 extends through thebottom of the valve body and through a guide 228 mounted on bracket 2I2.A connecting rod 229 is pivoted to the lower end 5 of the rod 221 and toa lever 239 which is pivoted at 23l to a bracket 232 secured to cylinder2 and has its free end 233 engaging the bottom end of the lower rod 2I5oi the piston 2I3. A tension spring 234 connected to the lever 239 andto the bracket 232 maintains such engagement.

The operation of the construction above described for Figs; 14 and 15 isas follows: Assuming the parts shown to be in their positions for thenormal desired height of the body with re- 15 spect to the wheels thesupported load is transmitted through the body of compressed airretained in the cylinder space above the piston 2l3. If the load on thevehicle is increased the cylinder 2| I along with the frame 2I9 of thevehicle 29 body will tend to descend with respect to the wheel. As aresult of this the lever 239 will be caused to swing upwardly about itspivot 23L thereby urging upwardly the valve piston 224 2 within thevalve casing until the port 225 01' the 25 supply line is put intoconnection with the port 22I of the operating cylinder through theintermediate space between the two portions of the piston 224. Theadmission of the. compressed air from the supply line into the cylinderspace v above the piston 2I3 causes the body to be raised with respectto the wheels until the position of the parts as shown in Fig. 14 isrestored where- I upon when valve piston 224 has closed the port 225 theheight of the body for that load will be maintained with respect to thewheels.

If there is a material decrease in the load on the vehicle the cylindercasing H I will tend to rise with respect to the piston 2 I3 whereuponthe lever 239 will be caused to swing downward about its pivot 23 l. tomove the valve piston 224, downward in its casing until the vent port229 is put in connection with the cylinder port 22! so that air isvented from the operating cylinder until the cylinder casing 2III alongwith the vehicle body is caused to descend with respect to the piston2I3. The descent continues until the valve piston 224 has been returnedto the position of Fig. 14 where by the operation oi. lever 239 the ventport 226 is again closed.

From the foregoing description of the several illustrated embodiments ofthe invention it will be seen that many of the phases of the inventionare applicable to suspensions generally whether they be of mechanical orpneumatic-spring operation or other type, and that the control of theheight of the body with respect to the wheels may be effectedelectrically, hydraulically, pneumatically and even manually. Also theoperation may be fully automatic, it may be automatic under manualcontrol or the operation may be effected manually.

Variations may be made without departing from the invention as it isdefined in the follow claims:

I claim:

1. A vehicle suspension comprising a plurality of wheel assemblies, asupported structure,

mounting means connecting the supported structure and wheel assembliescomprising a plurality of arm structures adapted to transmit supportedload, and means mounted on the supported structure cooperating with saidarms to transmit load thereto, the load transmitting means comprisingmeans for adjusting the vertical posembly, a supported structure,springing means between the wheel assemblyv and supported structurecomprising inner and outer relatively rotatable elements connected oneto the wheel assembly and the other to the supported structure, a bodyof rubber-like material mounted radially between said elements to eilectspringing by torsional stress on said body, and power means and acontrol therefor operable from the supported structure while the wheelassembly is under load tor rotatively adjusting one of said elements tovary the relative vertical positions.

of the wheel assembly and said structure.

3. A vehicle suspension comprising a wheel assembly, a supportedstructure, springing means between the wheel assembly and supportedstructure comprising inner and outer relatively rotatable elementsconnected one to the wheel assembly and the other to the supportedstructure, a body of rubber-like material mounted radially between saidelements to eflect springing by torsional stress on said body, and meanscontrolled at least in part by the height or said structure with respectto the wheel assembly for rotatively adjusting the elements connected tosaid structure with respect thereto for maintaining the height 01' saidstructure with respect to the wheel assembly approximately constant uponchanging the amount of load on the vehicle.

4. A vehicle suspension comprising a wheel assembly at each side of thevehicle, a supported structure, respective springing means between eachwheel assembly and the supported structure each comprising inner andouter relatively rotatable elements, one of said elements of each eflectspringing by torsional stress on .the rubber, an arm on each springingmeans extending from the element that is mounted upon said structure,and means on said structure common to both arms for adjusting them andtheir connected elements of the springing means simultaneously to varythe vertical position of said structure with respect to both wheelassemblies together. a

5. A vehicle suspension as defined in claim 4 in which the adjustingmeans common to both arms comprises means i'or adjusting the armsindependently and power means for adjusting the arms together. 1

6. A vehicle suspension comprising a wheel assembly, a supportedstructure, a springing mg, and power means on said structure operablewhile the'wheel assembly is under load for rotatively adjusting thebushing to vary the relative vertical positions of the wheel assemblyand said structure.

7. A vehicle suspension comprising a supported structure, a wheelassembly at each side thereof, respective mounting means connecting thesupported structure and each wheel assembly, each comprising an armstructure adapted to transmit supported load, and means mounted on thesupported structure common to both arm structures for transmittingsupported load to said arm structures, the last-mentioned means beingadjustable to vary the vertical position of the supported structuresimultaneously with respect to both wheel assemblies through said armstructures and adjustabie to vary the vertical position of a wheelassembly with relation to the other.

ALVIN S. KRO'I'L.

